Open
Cached
·
1h ago
75/100
SECURITY SCORE
Detected Technologies
Certificate Information
Subject
CN=lettersender.app
Issuer
C=US, O=Let's Encrypt, CN=E7
Valid From
February 19, 2026
Valid Until
May 20, 2026
21 days
Public Key
ECDSA
256 bit
(P-256)
Adequate
Signature Algorithm
ECDSA-SHA384
SHA-256 Fingerprint
29:0D:85:15:BE:21:E7:8E:64:D6:9F:05:01:89:DB:3F:51:6E:46:10:E3:63:C2:78:30:6D:0F:A4:31:F4:1F:10
Alternative Names
Security Configuration
TLS Protocols
TLS 1.2
TLS 1.3
Forward Secrecy
Supported
(Modern clients use PFS)
HTTP Security Headers
Status
Strict-Transport-Security
Good
max-age=63072000; includeSubDomains
X-Frame-Options
Missing
Not configured
X-Content-Type-Options
Missing
Not configured
Referrer-Policy
Missing
Not configured
Permissions-Policy
Missing
Not configured
Recommendations
- • Consider adding 'preload' to HSTS for maximum security
- • Add Content-Security-Policy header to prevent XSS attacks
- • Add X-Frame-Options: DENY or SAMEORIGIN to prevent clickjacking
- • Add X-Content-Type-Options: nosniff
- • Add Referrer-Policy header (recommended: strict-origin-when-cross-origin)
- • Consider adding Permissions-Policy to control browser features
CAA Records (Certificate Authority Authorization)
CAA Records
Not Configured
(Any CA can issue certificates)
CAA Issues
- • No CAA records configured - any CA can issue certificates
Recommendations
- • Implement CAA records to restrict which CAs can issue certificates for your domain
- • This adds an extra layer of security against unauthorized certificate issuance
- • Example: Add CAA record 'example.com. CAA 0 issue "letsencrypt.org"'
- • Consider adding 'iodef' record to receive security incident reports